1. Field of the Invention
This invention relates to a process of manufacturing slide frames which are preferably adapted to be elastically expanded and are made from at least one extruded plastic sheet plastic web, wherein plastic web portions are adhesively joined or joined by ultrasonic welding to form a frame and picture gates and punching operations are performed to form picture gates in the frame and to form the external contour of the frame.
2. Description of the Prior Art
In a known process of that kind the frame is made in that three sheets of extruded plastic are adhesively joined. The intermediate sheet is formed with a punched film bed for holding the slide. The sheets are first punched to form the picture gates and the film bed and are then adhesively joined and finally punched to form their outer edges. In the known process the processing of three plastic sheets requires a rather expensive apparatus comprising three supply rolls, three pairs of pinch rollers, two joining devices and one printer. The apparatus is succeeded by a packaging apparatus for packaging the slide frames in shrink film. The known process is complicated because the slide frames are made from three webs of sheet plastic.